High-power pulley-drive.



A.. L. DE LEUW.

HIGH POWER PULLEY DRIVE.

APPLICATION FILED MAY I. 1913.

Patented Dec.' QI, 1915.

3 SHEETS-SIIESI l.

Wham

faQ/Qdi M A. L. DI/LEEUW. HIGH POWER PULLEY DRIVE.

APPLICATION FILED MAYI, 1913.' v I 1,165,369. Patented 11110.21, 1915.

3 SHEETS-SHEET 2.

A. L. DLEEUW. HIGH POWERIPHLLEY DRIVE. APPLICATION FILED MAYI, 1913.

3 SHEETS-SHEET 3.

UNITED STATES PATENT OFFICE.

ADOLPH L. LEEUW, OF CINCINNATI, CHI()l` ASSIGNOR TO THE CINCINNATI MILLING MACHINE COMPANY, F OAKLEY, CINCINNATI, OHIO, .A CORPORATION OF OHIO.

HIGH-POWER PULLEY-nnivn.

. To all vuilziom t may concern ,Be itfknown that I, ADoLrH, L. Dn LEEUW,

a citizen of the United States, and residing i at Cincinnati, in the county of Hamilton andA State of Ohio` haveinvented va new and YIii-aproved High-Power Pulley-Drive, of which the following specication is a full disclosure.

nfersfor quick manipulation all in a compact self contained relation with lthe machine tool-lenabling the usual cone-pulleys on the -usual counter-shaft to be dispensed with,

while affording an equally .extended-yet more immediately available speed range.

This ,invention also contemplates an arrangement for increasingI the wei-king capacity ofa'belt-driven machine tool by pro- 'viding a pair-of cone-pulleys built into the machine, thus. providing for accuratej and firm bearings'permitting high speeds, and

providing speed reducing gearing between' the pulleys and the spindle, preferably including suitable intermediate -speed changegears, in'sueh a ratio -thatth -normal speed o f the 4initiall powerreceiving pulley will `greatly exceed that heretofore used, .although maintaining conventional speeds at the spindle; thereby-reducing the torque andl enabling narrow belts to be used and even augmenting the power transmitted.

I It is also an objective to `create a fewpart, compact and durabl'spleed-change systeni by embodying a cycle-leven having an elementary movement such as a pure rotation (as distinguished from combined movemetsl'and which when turned into itssuc-l cessive positionswill yield progressive lspeed increases, or multiples thereof, andV also embodving one `or more supplementary multiplierl levers adapted individually-or inutually to determine the mnltipleof the speed increases afforded by lsaid cycle-lever; thus relievingthe operator from the necessity of both shifting and rotating a single lever, and enabling him, for example, by advancing the cycle-lever intoY its successive positions, to shift the belt of suitable cone-pulleys to attain progressively the first few speeds of J'the range available,- as speeds `Specification of Letters Patent.

Application filed May 1, 1,913. Serial No. 764,829.

multiplier levers into their second position, to enable the cycle-lever to be advanced progressively to attain the next speed series in uninterrupted sequence, vas 'the speeds pulleys conversely arranged in cl oseprox imity in a gear box, the one cone-pulley i lhaving aldriving pulley arranged beyond the end of the other, and ther other having a live shaft extending through the frame tothe part to bedriven thereby; together with convenientA ,belt shifting and tightening features.

, Other objects and advantages will be in part indicated in the.following description .y and in part render-ed sufficiently apparent therefrom in connection with the annexed n drawings.

To enable others skilled in the art so fully to apprehend the underlying featureshereof that they may embody the Saineinthe various ways contemplated by this invention, drawings depicting a preferred typical constructionhave been annexed as a part of.

this disclosure, and in such drawings like characters of reference denote corresponding parts throughout all the views, of which:-

'Figure -1 is a side elevation 'of a speedchange box embodying this invention, showing. the belt-shifter and ge'ar-shifters as related in this arrangement. Figi 2 is an end elevation of the partswithiii the casing looking to the left of line 2-2 of Fig` 1, showingcmore especially details Aof the belttightener and gear-Shifters. Fig. 3 is an end elevation looking to the left of line 3 3 of Fig. l, showing details of the belt-shifter andof the friction-brake.. Fig. 4 is a detail of a Vratchet-brake used toA maintain the belttightener under anyjselected tension. Fig. 5 is a diagrammatic view with the parts intersected -by the tortnous line 5-5 of Fig. 2 laid out in a flat plane to show the relations of the parts to one another; showing all parts related to yield 'the slowest drive of the spindle. Fig. 6 is a speed chart.

Continuing now by way of ainore detailed description of the form of this invention herein illustrated, it will be understood thattliougli it is shown in connection with a milling machine, it may readily be adapted t0 yielding other types of machine tools, and for sundry purposes certain sub-combinations thereof may be used without others.

To give Others at the outset a more intimate insight into certain characteristic relations of elements vof this invention, will better enabley the distinctive' capacities of the illustrative structural embodiment thereof toI be comprehended. In the case of a milling machine, for example, it is very desirable to enable the speed of the spindle to be varied throughout aivide range, so that the speed best suited for any given cutter and working condition may be selectively available, and it is of prime importance that Athis desideratuni be attained without struc;

tural complexity. Preferably, the speed ra` tios should'progress ina geometrical ratio.

lAssume that the speed S of the first-'driven element is to be ment from S to by if changes or varied at .the last-driven ele- 06S (or anymultiple of S) steps in a geometrical ratio. lf. r represents the constant multiplier, then Sryl .00S Yand N' r=y 1dr.

Concretely, if V1G changes are desired,l and the spindle range is l `to 20, then a: 151% or 1.22,

To attain these changes, this invention proposes a friction change-uint yielding' a sub-series of speeds constituting a coinmondivisor ofV the total. available changes, combined in a self-contained relation with one or more change-gears arranged in multiple series therewith and proportioned to intro-V duce such multipliers will enable the lfull range to be had. Let the friction unit yield 'a changes (say four), and suppose a pair of two-step speedchange gears be combined therewith. rfhen the values of r for the friction unit will'be roe-rL-rl` (it-W* rzw'i); the values of r for the lirst speed change gear may be r and rml (r and ri) and the values of r for the second speed change-gear may be roand r2 ('r" and rg) gy the full specdrange. Making the lowest value of r of onel of the speed change gears equal to unity (7) enables it to take the simplest structural form, as a back gear givingone direct drive. It will be noted that the high ratio equals r. times the low ratio in the first speed change-gear, and r2" times the low ratio in the second speed change-gear. 1 i In its more intensive aspect, this invention also .proposes .a further proportioning of speeds between the. several compoi'iei'it sp change ,units constituting thetransn'iissionv ti i,

llhatis to say, the spindle speed may, cimtorniing with .modern shop practice, 'entre from say 20 to :4r-OO it. l. lll.; but it is va uta ges will intended to run the friction-unit at a very much higher speed, say 1300 more or less; and also to i'un the change-gear at an intermediate speed fast enough to insure easy shifting and permit of comparatively lie'ht gears, yet slow enough not to induce chatter or vibration. To this end, speed-reductioii gears will preferably be arranged between the frictioneunit and the speed changegears; as well as between the speed change-gears and thev spindle. It is, apparent that lsuch intermediate speed reductions may be introduced in various ways into the transmission. ln the light of this explanation, the. various mechanical characteristics whereby these proposals niaybe put into practical eilect will now be made clear b v au analysis of the following structural example.

rl`he frame may advanti "eously be constructed iii two parts such as the main fran'ie l of the machine in which jouriialed the spindle and is mounted the overarm, and the box-frame 2 bolted thereto and containing;` as a unit the features whereby dilferent speeds are .transmitted to the spindle, thereby pron'iotinkg` accuracy in the mounting,` and relations of the change elements.

Ait one end, theboX-frame 2 is open to receive a chain or belt S3 driven by a suitable external'power-pulley (not shown), which belt passes around a pulley supported at one end by the inner wall of the boxfraine and at the other end. by a cap plate -t attached to the open end of the box-frame. lItis noteworthy that this frame together with 'the friction change units and the speed changegears mounted therein constitutes a self-contained speed-change structure of a peculiar internal arrangement'. 'p Many adbe apparent, but the superior lubricating facilities otl'ered thereby 'for higli-speed pulleys is worthy of consideration.

rlhe high-speed low-step cone-pulleys form elements of a Afriction-drive speedchange unit and are indicatcd'hy and (i respectively, and are mounted in the boX- traine 2 near one eud thereof. These puls `leys are typical of two members, -one of' which zimpositi vely drives the tion` Aas distinguished from positive-drive gearing. The conc 5 is preferably longer than its companion and, i'l npt directly connected to a power shaft, will prefi-irably integrally provide a main pulley 7 located laterally beyond the end ot the pulley (i, and ladapted to receive the'maiii drivingr belt fl. ln this instance, the pulley 5 provides four steps fr, E), c, and d, which arebut slightly graduated in diameter from one another and are connected by conical merging surfaces. These steps are opposite corresponding steps d', c and d of the companion pulley (l. A grooved wheel 8 .may also be carried. as 'by the pulley 5 and used for the other hy fric- 1 .12il'land 1135 for gr/ gi and trespeg-` purpose of driving some auxiliary appliance', such as an oil-pump. The companion pulley 6 is preferably keyed to a live spindle 9 that extends through' and is journaled .in a boss 10 projecting from the frame; the reduced end of the driven pulley being preferably positioned toward the main driving open'belt 11-may -be used to transmit motion` in properratio from the one step to the'other, said belt being adapted to shift from step to step assisted by the conicalsurfaces, to give .thedesired speeds. In this instance, the diameter ofa and d is 4.63; of b and c isv 5.13, ofc and b. is 5.75." and of d and af .is 6.25.5 thus yielding the, ratios .74 .89"

tively, which is a series very closely con- The tor'que-varying and brakingl lever is denoted by 12 and is indicative of ahandoperated member of any suitable configurationand located on the machine-tool near the point at which the tooling is being done, so that the operator may have his hand con! sta'ntly on the control-lever eitherto discon-l neet/the power and impose friction to terminate more quickly the rotation of the spindle, or progressively to increase the drivlng ltorque from zero to any desired degre'e- "all while' he is in whatever-station.' he `may haveselected close .tothe work to enable him to watch the progress of the cutting tool to ,the best advantage. This lever has its hub journaled to a verticalshaft 13l which pro- ]ects above the right-hand end vof the box 2, and it may be adjustably'locked in any position to such -shaft by permitting its teeth' 14. toengage with corresponding teeth noteworthyfthatthis'mounting. ofthe pulley i on a collar 15 fixed toltheshaft, By rocking the shaft 413, the-distance between the cone `pulleys may be varied thus 'loosening .or

tightening the driving. belt therebetween, and this eect is obtained by means of the following construction.

The shaft 13,`after entering the interior of the bo'x 2, terminates in a beveled gear 16 keyed thereto and ymeshing'with a gear 17 pinned to the horizontally. extending shaft 18, which is journaledat 19 and 2O (see Fig. 5)` and between vthese' journals;eccentricallyl carries a shaft-21fserving. asjax dead- "spindle, upon which the conepulley 'revolves. f 1t is 5 permits-,ofainple lubrication and enables it,to run at veryhigh speeds.l 'By rotating the shaft 18,. `the axis fof the eccentrically positionedffshaft 21,'.is `of course swung in 'a wedge-shaped pin-plunger 23 is spring,-

a`local hard spot be reached temporarily `12 shall alsdhave the 'capacity'of more circle, this varying the distance of the pulley 5 from the. pulley 6. Preferably, a Y ratchet brake imposes resistance to the vmovement of theshaft 18, and enables the parts to maintain the position into which theyv are set by lever 12.- This brake 4consist of a segment 22 having its Iperiphery corrugated and secured to move tion of the tooling operation, and yet by reason of the adjustability of the handle 12,

he may have the transmission of. power un# 8 5 der. instantaneous and sensitive control. f Thus, he may move handle 12 to a point just adequateto insure a drive of the cutterfor normal working conditions, and yet should .90 requiring unusual power, a momentary push on the handle 12 will enable the belt 11 to be tightened, t'o a degree overcoming thel un usual torque, so' ,that the machine may operate for` short intervals under emergency' conf ditions, thus giving itI a greater average capacity. ln its preferred specific Vforni,it is -proposed that this, same ,hand-operated member quicklyl terminating r the 'rotation of the spindle when urged by pressure into one of l its two extremities of movement. To enable this to be done, a friction-brake is arranged atsome point in the transmission, preferably in coperation with a high-speed element 5thereof,-as the pulley 6, and constructing n2,1 andh'aving a boss 38 adapted to contact v1.15

with the pin 39'projecting from the arm 36, whereby its angular position may7 be Vdetermined. Th'isarm 36 terminates in ay V- shaped fricti'h me'mber 40 that rubs against 4the V-Sh`aped'periphery of the flange `11 in- 12o tegral with the pulley '6. Byr this-means frictionis imposed impeding the. rotation of the pulley lG-Whenever the belt 11 isloosened by the approach of the pulley 5 so as .more

'quickly to cut down'j the rotation of the 125 spindle. By reason of this construction, the shaft 18 may be rotated through 180,while the arm may move but a few degrees into 'a releasing or non-braking position, thus pio' meting compactness.

The speed-change cycle-progressing lever Iherein revealed has a very simple structure by advancing` the handle through its first cycle,r then throwinganother lever to introduce a multiplier, and then advancing the handle through its next cycle, and so on, all

the speeds of the system may be in turn attained. ln. this instance, this handle is mounted on a crank arm extendin,( from a shaft 20 extending into the interior of the change-box and which has a pinion 2T keyed to its inner-end in mesh with a rack 28, whereby a slide 29 may be reciprocatedj' upon the guide-rod 30, and caused to shift the belt 11 .by means of the wings 31, with 'which it is provided. At the four fixed points in the arc of movement of the handle 25 are suitable stops A-B-G and l), which, by suitable detent mechanism will temporarily maintain the position of the operating` handle 25 and indicate the several increasing driving ratios provided by the'belt 11 on the pulleys i5 and (i. The inimediate'effectof thus shifting handle 25 through the four stations A, B, C and D is to increase the i speed of thedriven-pulley (l in some desired series; as in the geometrical series 70-71- 93h71 of the illustrated .form whereof has a value of say`l22. Itis also notable that the intended constant speed of the pulley 5 is about1300 R. P. M. which in this Case would drive pulley G at about speeds 900, 1160, 11i-G0 and 1760 R. l). M. according to the step used for the connecting belt. This represents the first cycle of this lever, but during its next Acycle it should yield the speed se ries i"-r-r-r7 and to that end a multiplier il" (an) willhave to be introduced, and this accomplished by means of the following mechanism.

The'first cycle-fixing or multiplier lever is denoted by and has an operating handle 56 whereby it may be moved into station E (low ra'tio)-oi:' station F (high ratio) to in troduce. an appropriate multiplier into .the

' lspeed series afforded by .the last mentioned lever to shift its eifective cycle. The shaft 9 carries a gear 42 (18 teeth) at its extremity; .which is constantly in mesh with a second gear 43 teeth) that drives the first gear-change element 4G. llt is to be noted in this connection that the pinion 4t2 in mesh with gear effective to reduce the speed of themotion.transmitted to the first gear,

structural simplicity.

proposed to utilize a back gear arrangement change element so that the shaft 9 may be rotated quite rapidly, thereby decreasing the torque necessary at the pulleys to enable them to transmit a given power. Acompact two-step gear-shift is preferred and this consists of two shafts all and 45 that are mounted adjacent one another in the frame of the gear-box. The element 16 which is driven bythe gear :t3 is loosely mounted on shaft 1l and carries a small drivii'ig-gear e (30 teeth) yand a larger driving-gear j (44 teeth). Loosely mounted on the Shaft 45 is a sleeve -19 to which is splined a Second sleeve 50 carrying` a larger driveirgear e (lo teeth) and a smaller drven-gear j (3l teeth). By shifting the sleeve 50 in an axial direction, gears 7 and may be intermeshed, or gears e and e may be inter. ineshed, as desired. This gear shift is readily accomplished by means of a rock shaft 53, from which extends an arm 5K1: (Fig. l) having a forked end pivoted, thereto, and engaging the sides of the gear e, so that when said shaftris rocked by swinging the arm by means of the handle 56 into one of its temporarily restrained positions, the above-mentioned gearshift will be effected to change the ti/i'iii/ismission ratio as explained. It is (noteworthy that while the pulley in thisilpy n @uns attln-iveryhigh speed range of y all. 0 R. P. M. to 1775 R. l). M., the spoilt-hof the `ear element i6 only ranges from 5l() to- 99() or about one-half that of the belt-drive unit, andthe speed range of the gear element 50 has even lower limits. Thus, the speeds of the change-gear are very materially less than those of the cone-pulleys, while: yet@ as will be seen shortly, they are` materially greater than those of the spindle.

The second cycle-fixing or multiplier lever is operated by the handle G7 which is arranged on a lever and constructedin the manner already described in connection With' the handle 56. This second lever operates a second gear shift which by reason of utilizing values of fr" and r2 may embodya direct clutch drive of unity (ro) and thus inalie for To this end, it is which comprises a shifting part 58 splined to the shaft 45 and having the clutch teeth n adapted to engage with corresponding teethQ-zir 'on the sleeve 49, thereby effecting a direct driving Aconnection (r9) between the sleeve 50 and the shaft 4:5. In this positioih' a sleevel journaled on the shaft 44 is driven idly by the pinion G1. (19 teeth) secured to the sleeve 49 and which engages thel gear G2 (41 teeth) secured to the sleeve 60. In its other shiftedpposition, however, the teeth a. are disconnected from the teeth of the sleeve i9 and the gear g (4t2 teeth) is m'i'slied with the pinion g (18 teeth), on the sleeveO so that kpower is transmitted to vse pinion 64 (-16 teeth) that meshes With a gear 65 (56 teeth) keyed to the spindle G6 which is'suitably journaled in the frame.

.By virtue of this arrangement', the speeds of the spindle may be increased progressively in any desired ratio as for example in a geometrical ratio. Thus assuming the parts are positioned as shown by Fig. 5, the

`first four speeds. of the series are obtained by merely shifting the main lever through po- SitionsA, B, C and D, To obtain #the next Afour speeds, the handle 56 is shifted to posi- .tion F and. then the main lever is shifted progressively throughits four successive positions. By similarly .manipulating the three levers sixteen progressive speeds are available according 'to the chart shown on Sheet 1 of the drawings.

lVithout further elaboration, the' foregoing will so fully reveal the gist Vof *this invention that others can by applying current knowledge readily adapt it for various kapplications Without omitting certain 'features that, from the standpoint of the prior art,

-fairly constitute essential characteristics of the-generic or specific aspects of this invention,fand therefore such adaptations should and are intended to be comprehendefd within the meaning and range of equivalency of the folloiying claims l D Havingth'us described this invention, i

i claim as new anddesire to secure by Letters Patent of the United States l. A machine-tool organization of the nature disclosed combining a frame, a pair of pulleys each mounted in said 'trarne adpicent- 'one another, one if said pulleys being a stepconc-pulley, a belt connecting said pulleys, means for adjusting the proximity of said pulleys to tighten the belt, one of said pulleysgproviding at one end a plain pulley v"adapted to receive a main power-driven belt,

and machine elemeiitsinounted on said franiehaving a driven connection with the other pulley of said pair.

machine-tool organization of the na-r hture disclosed combining a frame, a pair of pulleys each mounted in said frame adjacent one another, one of said lpulleys being ay step-coiie-pulley, a belt connecting said p uljleys, means 'for-..adjusting the proximity of said pulleys totiglitenthe belt, one of said pulleys providing at one eind a plain pulleyl arranged at one -side ofthe'otlier pulley and adapted to receive a main p'oiif'er-driven belt, said ptlierpulley being mountedV on a Alive-spindle extending through said frame and terminating in a gear, and machine elements mounted on said frame having a driven connection with the other pulley of said pair.

8. 'A machine-tool Iorganization of the nature disclosed combining a framea livespindle mounted on Vsaid frame, a dead-spindle mounted on said frame, a pair of pulleys, the one fixed to said live-spindle and means operating in connection ivith"said' dead-spindlefor ,regulating the tension of said belt, and a plain pulley in unitary relation With one of said pulleys adapted to receive the main power-driving belt.

l. A machine-tool organization of the nature disclosed combining a frame, a rockshaft and al live-spindle'both journaled in said frame in proximity, said rock-shaft vhaving a bearing surface eccentric to its axis, a pulley journaledvon said` bearing surface, a plain pulley in unitary relation therewith adapted to be drivenby a power-belt, a pulley secured to said live-spindle opposite said first mentioned pulley, one of said last two mentioned pulleys being a step-cone-pulley, a belt connecting said pulleys, means forrock-l ing said shaft to tensin said belt, and niachine elements mounted on'said frame having a driven connection with said livespindle.

A ture disclosed ,combining a rame, a rockshaft and a live-spindle bot journaled in said frame in proximity, said rock-shaft having a. bearing surface eccentric to its axis, an armactuated by said rock-shaft, a pulley Journale-gl lon said Vbearing surface, a pulleysecure'd to said live-spindle, a lever machine-tool organization of the na-l for manually` .turning said rock-shaft to t vary the proximity of saidpulleys and simultaneously cause said arm to impose friction on the `pulley mounted on said livev spindle, a shiftable belt connecting said pulleys, power-driven means for rotating the pulley on said rock shaft, and machineelements mounted on said frame actuated rfrom said other pulley.

6` A machine-tool organization of the nature disclosed combining a driven machineelement. a power-receiving unit comprising high-speed cone-pulleys and'a main drivingpulley therefor, a change-gear interposed between said element and said high-speed unit, a speed-"reduction gear transmitting motiony from said unit to said change-gear, ,l and gearing connecting 'said change-gear with said4 driven machine-element.

T. A machine-tool organizationof the na-I ian .ture disclosed combining. a driven machineelement, a poner-receiving unit comprising liigli-speed cone-pulleys and a main' drivingpnllef,T therefor, between said element-s and said high-speed unit, and twospeed-reduction lgears, the one interposed between said element and said changegear and the other between said change-gear and said higlrspeed unit.

95A machine-tool organization of the nature disclosed con'ibii'iing' a power-receiving unit comprising liigli-speed cone-pulleys and a main driving-pulleytherefor, a lirst changegear, a second cl'iangegear, a driven niachine element, said parts being arranged in series in the order enumerated, and a speedrediiction gear interposed in series between two of said parts.

l0. A machine-tool organization of the nature disclosed combining a powerreeeiving unit comprising.,y high-speed cone-pulleys and a main driving-pulley therefor, a first changegear, a secondchang'eg'ear, a driven machine element, said parts being' arranged in series in the order enumerated, and a speed rediiction gear in series between said unit and said first change gear.

A11. A machine-tool organization ot' the nature disclosed combining' a `iower-receiving unit comprising higrlrspeet. cone-pulleys and a main driving-pulley tlierel'o'i, a iii-st change-gear, a second bange-gem; a driven machine element, said parts beine' arranged inl series in the order enumerated. and. a speed-reduction gear between saidniaeliineelement and said second changeavan 12.` A nature disclosed combining a po\\'er-receiving nnit comprising' high-speed coin-pulleys and a main driving-pulle-v therefor, a Iii-st ehaiigegear, a second cliaiigwg'eai', a driven machine element, said parts being arranged in series in the order enumerated, a speedredii tion gear between the high-speed unit the iii-st c:liai1""geai', and a second timed-reduction geaL between the second change-gear and the niaclii11e-element.

13. A machine-tool organization ol" the nature disclosed combining' a driven machine element, a power-receiving unit coinprising hie'h-speed 'friction-members and a main drivingpulleytherefor, aV change-gear -interposed between said element and unit,

and a, change back-gear between said change gear and said element.

lat. A macliiiie-tool organization of the nature disclosed combiningn a machineelement, a iiower-i'eceivinfg unit comprisingr high-speed frictionanembers and a main driving'qnilley therefor, said unit having a limited speed range of slightly graduated ratios, a changegear in "series with said iinit and having a speed-change step exceeding the speed i: nire of said unit, a back-gearin series with said chaiigegear having a speed a changegear interposed machine-tool organization of the ynature disclosed combining a reduction gearing arranged between said imit and said machine element, all of said parts being` in series. I

l5. A. machine-tool organization of the nature disclosed combining` a spindle, a po\\'er-dii ven member, a belt-di'ive iiiiit land suitable gearing forming a transmission ti'ain from said member to said spindle, means for adjusting the tension ot' said belt, a lever for controlling the operation of said means, and means for selectively determinin;` the normal position of said lever with relation to said means.

16ml. machine-tool organization of the nature' disclosed combining a spindle, a po\\'ei'driv -in member, a belt-drive unitaiid' suitable 4gearing' forming; a transmissiontrain from said member to said spindle, mams for adj listing the tension ot said belt, a trictioirbrakeiinpeding the movement of said means, and a hand-lever for operating; said means in opposition to saidV frictions). resistance. I'

li'. .t iiiacliiiie-tool organization' of the natni'e disclosed combining' a spindlley ay ppiveiedriven member, a 'belt-drive iinit and suitable rearing toi-ming' a transmission train Yt'i'oin said member to said spindle, means l'or adjusting' the tension of said belt, and a liaiid-lever located adjacent the worlt izi,e'-eiid ot' said spindle and adjiistably con nei-ted to said means ivlierebjr its normal posi ion relative to said means may be initially varied to enable,l said means to be actuated by said handle t'roin various positions selected by the attendant. 18. A machinatool organization of the nature disclosed combining' a spindle., a poner-driven member, a belt-drive iinit and suitable gearing forming' a transmission train from said member to said spindle, meansI for adjnstably determining the tension ot' said belt, a ratchet-malte Vt'or lvieldablyv maintaining the oosition of said means, and a hand-lever adapted v,tobt manually actuated to operate said means.

lfi. ,t machine-tool organization of the nature disclosed eombiniiig a spindle, a

power-driven member, a belt-drive ilnitand means lor adjusting the tension ol lsaid belt, means lor `lrii-tiona'lly in'ipedifng lree rotation ol' said train` a lever t'or controlling;r the operation ol both ot' said means, and means tor selectiveliY determining the noi'- mal position ol'l said lever with relation-tto said means.

2l). A machine-tool organization of the spindle, a power-diivw member. a belt-drire iinitaiid siiitable gearing 'forming a` transmission train from said member to said spindle, fri@ iis loll

lli]

tion-impeded means for adjusting the ten-- sion of said belt, means, for frictionally iinpediiig free i'otation ofsaid train, and a,

second means effective.

2l, A machine-tool'organization of the nature disclosed combining a frame,a`spin dle, a power-driven member, a friction-drive unit and positive-drive gearing forming a speed-reduction transmission train from said member to said spindle, means for varying the.driving-friction of said unit, a device for yieldably maintaining said means in any predetermined position, an operating-lever for actuating` said means and adjustably connected therewith whereby its normal position relative to said means may be initially' varied to enable the neutral station of said lever to be set at any. predetermined point in the arc of movement of said, lever, and brake-mechanism for impediiig rotation of said tain actuated by said lever during its movement away from its neutral station.

22. A machine-tool organization of the nature disclosed combining a power-driven member, an ultimately-driven member, a

transmission traiii therebetween comprising a high-speed friction-drive change-unit, a multiple series of change gears, means for regulating y the v di'ivingfriction of said change-unit from zero progressively to a predetermined maxi-mum, a friction-brake for impeding` the free rotation .of said transmission t `ain, a single member having a han- Idle located closely adjacent the working end of said ultimately-driven member and connected with said friction controlling means whereby in one extreme position said friction-brake will be` made operative and adapted when moved toward its other extreme position first torender said brake inoperative and progressively augment the driving capacity of said friction-unit; and a frame mounting all of said part-s to form a self-contained struct-uralentity.

23. A speed change organization, of the nature disclosed combining a power-driven highspeed friction speed-change mechaiiism, a shift means varying the transmitting speed thereof by closely graduated steps, a positive-drive change-gear'geared in multiple series to said mechanism, .a spindle driven by said organization, and two speedv reduction gea'rings, the one between said friction-mechanism and said change-gear, and the other between said change-gear and said spindle.

24. A speed-change organization of the nature disclosed combining a power-driven high-speed frictionspeed-change mechalnism, a shift means varying the transmitting/speed [thereof Iby .closely graduated steps, a positive-drive change-'gear geared to said mechanism, a second ,positive-drivex' change-gear in multiple series with said first' change-gear, a` spindle driven by said organization, and two speed-reduction gearings, the one between said friction mechanism and said first change-gear, and the I said change-gear, a spindle driven by said organization, andY two speed-'reduction'gear-l ings, the one between said .friction mechanism and `said first clia,ngegeai','and the other between said second change-gear and said spindle.

26. A speed-change organization of the nature .disclosed combining a power-driven high-speed friction jspeed-changemechanism, a shift means varying the transmitting speed thereof by 'closely graduated steps,I a positive-drive two-shiftfchange-gear geared to said mechanism,A a second positive drive two-shift change-gear in multiple series therewith and having its low-shift, ratio equal to unity, a spindle driven by said organization, and two speed-reduction gearings, the one between said friction mech. anism and said fiist change-gear, and 'the other between said second change-gear and said spindle. l

27. A unitaryI machine-tool organization of the nature disclosed combining in compact relation a friction speed-change unit, a shift means varying the transmitting speed thereof by n slightly 'graduated steps in geometrical progression, a positive-drive rchange-gear geared in series with said unit adapt-ed to be shifted tomultiply its own lowest transmitting speed by a factorofrthe value fr, where r is the constant multiplier of the said gepiiietrical progrcssion, and means for utilizing-said organization for transmitting power. A unitary machine-tool organization of the nature disclosed combiningin compact relation a friction speed-change unit, a shift means varying the transmittingV speed thereof by a slightly, graduated steps iny geometrical progression, a positive-drive change-gear geared to said unit adapted to be shifted to multiply its own lowest transmitting speed by a' factor of the value fr, where r is the constant multiplier of the said geon'ietrical progression, asecond positive-drive change-gear in series with said first change-gear and adaptedto be shifted to multiply its lowest transmitting speed by a facto-r of the value r2, and means for util'iling said organization for transmitting power. y

29. A unitary machine-tool organization of the nature` disclosed combining in compact relation/a friction speed-change unit, a I"shift means varying the transmitting spiied thereof by a slightly graduated steps in 'geometrical progression, a positive-drive two-shift change-gear geared to said unit and having its high-shift ratio equal to r times its own low-shift ratio, where r is the `constant multiplier of the said geon'ietrical progression, shift means for operatingsaid change-gear, 4and means for utilizing saidorganization for transmitting power.

$30. A unitary machine-tool airganization of the nature disclosed combining` in coinlpact relation a friction speed-change unit,

a shift means varying the transmitting speed thereof by n slightly graduatedsteps in geometrical progression, a positive-drive two-shift change-gear geared to said unit, and having its high-shift ratio equal -to fr times its low-shift ratio, where 7" is the constantmultiplieiof the said geometrical progression, a second positive-drive two-shift change-gear in f series therewith andhaving itslow-shift ratio equal to unity 'and its high-shift ratio equal tor, andineans for utilizing' said organization` for transmitting power. l l i 31.3K unitary machine-tool organization of thenatin-e disclosed combining ya unitary power-driven vfriction speed-change mechanism, a, shift means varying. the transmitting speed thereof by n slightly graduated steps in geometrical progression, a positivedrive change-gear geared in series to said mechanism adapted tobe shifted to multiply' its lowest transmitting speed by a fac` tor of thevalue r, where Ir is the constant multiplier of the said geometrical progresist ' sion, a spindle driven by said organization,

and speed-reduction gearing between said mechanism and said spindle. i

32. A unitary .machine-tool organization of the nature disclosed combining a unitary power-driven friction speed-change mechanism, a shift means varying t etransmitting spveedthereof by n slightly 'graduated steps' in geometrical progression, apositive-drive change-gear geared to said mechanism adapted to be shifted to multiply its .lo west transmitting speed by a factor of tlie'value ru where 11 isv the constant multiplier f the said geometrical progression, a second positive-driveA change-gear in series with said first change-gear andl adaptedto be shifted to multiply its lowest transmitting speed by a factor of the value r2, by said organization, and' speed-reduction gearing between said mechanism and said spindle.

33. A unitary machine-tool.organization 0f tlie nature disclosed' combining' a unitary ,geoiiietrical progression,

a spindle driven power-driven friction speed-change mechanism,a shift means varying the transmitting speed thereof by a, slight-ly graduated steps in geometrical progression, a positive-drive two-shift change-gear geared to said mechanism and having its high-shift ratio equal to r times its low-shift ratio, where i' is the constant multiplier of the said geometrical progression, shift means for operating said change-gear, a spindle driven by said organization, and speed-reduction gearing between said mechanism and said spindle.

3i. A unitary machine-tool organization. Y

of the nature disclosed combining' a unitary power-driven friction speed-change mechan-ism, a shift means varying the transmitting speed thereof by a. slightly graduated steps in geometrical progression,- a positive-drive two-shift change-gear 'geared to said mecha.- nisiii, and having its high-shift ratio equal to r. times its low-shift ratio, where r is the constant multiplier of the said geometrical progression, a second positive-drive twoshift change-gear in series therewith and having' its low-shift its high-shift ratio equal to r2, a spindle driven by said organization, and speed-reduction gearing between said mechanism and said spindle.

A machine-tool organization of the nature disclosed combining-a unitary powerdriven friction speed-change mechanism, a shift means Varying the transmitting speed thereof by n slightly graduated steps in geometrical progression,

nisin adapted to be lowest transn'iitting speed by a factor of the value r, where r isthe constant multiplier of the said geometrical progression, a spindle drivenvby said organization, and two speed- `reduction gearings, the one between said mechanism and said changegear and the other between said change gear and said spindle.

36. A machine-tool organization of the nature disclosed combining' a unitary powerdriven friction speed-change mechanism, a shift means varying the transn'iitting speed thereof by n, slightly' graduated steps in a positive-drive change-gear geared to said mechanism adaptto` multiply its lowest transed to be shifted mittingspeed by a factor of the value r,

where fr, the constant multiplier ofthe said geometrical progression, a. second positivedrive change-gear in series with said rst change-gear and adapted to be shifted 'to multiply its lowest transmitting speed by a factor of the valuefrz, a spindle driven by said organization, and two speed-reduction gearings, the one between said mechanism and the first change-gear and the otherbetween said second change-gear and saidA spindle.

ratio equal to unity and a positive-drive' change-gear geared in series to said mecha-l shifted to multiply its' iio ' shift change-gear geared to said mechanism and having its high-shift ratio equal to r times its low-shift ratio, where r is the con-- stant multiplier' of the said geometrical progression, shift means for operating said change-gear, a spindle driven by said organizatioin and two speed-reduction gearings, the

one between said lmechanism and said change-gear andthe other between said change-gear and said spindle.

38.' A machine-tool organization of the na- .'tnre'disclosed coinbininga' unitary powerdriven lfriction speed-change mechanism, a shift means varying the transniittingjr speed thereof by n slightly graduated steps in geometrical progression, a positivedrive tivo-shift change-gear geared to said iiiechanisni, and lia-ving its high-shift ratio equal to 7 tinies its low-shift ratio, where r is the constant iiiultipliei-oil said geometrical pro'- gression, a second positive drive tivo shift change-gear in series therewith and having its low-shift ratio equal to .unity and its high-shift ratio equal to r2, a spindle driven by said organization, and tivo speed-reduction geni-ings, the one between said mechanisiii and the first change-gear and the other between said second change-gear andsaid spindle.

ln witness whereof, I hereunto subscribe my naine, as attested hy the two subscribing witnesses.

ADQLPH L. DE LEEUW'.

Witnesses Onivnn B. laisiin, ALnnR'r F. Wa'rimN. 

